Genomics 101
For hundreds of years, humans have been altering the DNA and genetically modifying foods and animals for our selfish gain. We are soon and quickly reaching the point at which we will be able to use gene therapy or genetic modification in humans to help us live better and longer lives!
Since the time of Gregor Mendel, hot take: the most interesting botanist, humans have been obsessed with understanding heredity and with understanding how to recreate specific traits within living things. Our study of life and heritage branched off into a new more modern study called genomics in which we humans have been learning about genes and the most fundamental building blocks of all life, DNA.
In today’s world, our need for new technologies with the implications to change the genetic code of life is what we need as resources to our problems as they get more difficult. Through our research, we have begun to realize how we can use our understanding of genomics to cure some of the most sophisticated diseases, which is why we must come together to decide on current ethical dilemmas. I want to discuss some of the most important details so more people will be able to take a more educated stance on the topic.
A quick reflection to see how much you know about cells…
Finish the following phrase: The mitochondria is the __________ of the cell.
If you got the answer, you really are a powerhouse of knowledge!
Original Genetic Modification
First, let’s begin by understanding the status quo of genetic modification. The term genetic modification probably sounds familiar because it makes up the first two parts of the acronym GMO. A GMO is a genetically modified organism and it has been going on directly or indirectly for thousands of years. Genetically modifying food was a selective method of breeding that farmers took advantage of to increase crop yields and Americans have used to eat more. I guess you would call this a symbiotic relationship… But seriously, people have been passing on favorable traits and genes that they would find in some plants by replanting the “better” plants and making sure that the worse off plants did not plant their seed.
This same thing happened with horses as well, when you would find a fast horse or a desired trait in a horse that you would want to pass on to a new generation, you would breed that horse with another horse to hopefully have that trait in the foal — baby horse. To increase the chances, breeders would even breed the desired horse with a horse with the same trait to have an even higher chance of success. This could happen with any assortment of traits like the fur color, eye color, and even the horse’s speed. When people train horses for racing, they start by first paying tonnes of money just to have a desirable breed with advantageous genetics and then worry about the actual training later. This is a brute force strategy to breed a desired horse as this is not guaranteed and there are chances that the trait is not passed on depending on the nature of the gene. This is where our more modern approach of genetic modification comes in.
Modern Genetic Modification
In the more modern science of genetic studies and modification, we talk about a much more different approach to genetic modification, genetic editing. Now, my goal with my following explanation is to help you understand genetic editing in the most basic but in-depth way I can so let’s start with some basic definitions that will be helpful to us.
The cell is one of the smallest units of life and the smallest structure in the body. Everything we talk about has to do with the cell. The genome is made up of genes and is basically each person’s unique set of genetic codes within the nucleus of a cell. Genes are specific sequences of DNA within the nucleus that coil up as chromosomes during cell processes. DNA is the double helix-shaped molecule that carries all types of genetic information. DNA is made up of the most fundamental building block of genes called nucleotides, over 3 billion nucleotides exist in the human genome. Nucleotides are what make up individual variance because they are comprised of base pairs. Base pairs are the small difference between nucleotides and the types of pairs include the A, G, C and T base pairs. Each base matches up with its base counterpart which is why it is called a pair.
That was hopefully the most boring part so let's get into the interesting stuff about how we can use this.
Very recently in 1993, the genetic engineering field had its first major breakthrough. Francisco Mojica was one of the first researchers to characterize CRISPR. CRISPR is the adaptive immune system used by bacteria to combat infections created by viruses. When the bacteria senses the DNA of a virus, the bacteria expends two RNAs. The RNA’s goal is to help find the part of the DNA the cell wants to break and guides a specialized protein called CAS 9 to that spot to snip the DNA.
By the way, CRISPR is an acronym for Clustered Regularly Interspaced Short Palindromic Repeats which you will probably never need to know but here it is in case.
If that was too much information to digest, let’s go into it more slowly. RNA are molecular machines in the cell that does work, this includes but is not exclusive to moving things, begins and ends operations, and relays information from the nucleus to the rest of the cell. To create proteins such as CAS 9, DNA from the nucleus is transcribed onto RNA, sent to a ribosome which now has an architectural blueprint on how to create the protein. Then another type of RNA comes and drops off amino acids to create the protein and after some time a cell creates CAS 9. CAS 9 is a protein that bacteria use to replace, paste or delete information from DNA and is the main protein currently used for most genetic editing purposes. For its use as an immune system, CAS 9 usually deletes and breaks apart the virus DNA so that it is no longer affected by it.
Today’s Implications
As we learned more about the cutting edge CRISPR system used by bacteria, we have begun to think about the applications on humans. We began to explore the possibility of editing genetic data in humans by sending these CAS 9 proteins along with its RNA to change some of our genetic data. Some of the implications of this new tech have been put in the public eye because we can also change genes that contribute to aesthetics. Our main goal is fixing diseases but because aesthetics are an option to edit, people have begun to think that the technology as a whole is crossing the line.
One of the coolest but also most weird concepts that have come out of this new technology is called designer babies.
Imagine looking into the embryo of a human baby while still in the womb and figuring out how each nucleotide affects every aspect of that baby, this is called mapping or sequencing. With this amazing ability to sequence the genes of embryos, with the help of CRISPR, we get the opportunity to completely change the way the baby is created. We could potentially hard code babies to the exact specifications of the parent which has really seemed to open up a conversation with society.
Sequencing genes is another super complicated but interesting process of mapping the DNA of genes, it is useful when trying to find parts of the genome affecting certain traits. Without knowing the sequence of your genes you would never know what nucleotides you want to change or delete.
Genes such as eye color, skin color, and even how many brain cells your brain will create by the time it is completely aged are dependent on your genes. Some of the variances in genes can be catastrophic, such as sickle cell anemia, a condition in which your body does not have enough healthy blood cells to carry oxygen. Some of these diseases are genetic diseases and are as simple to solve as changing one nucleotide, AKA single nucleotide variant diseases. With our newfound ability to edit people’s genes, we could go into embryo’s and change the very code of a baby to create a designer baby. This is considered a designer baby as its genetic makeup has been selected or altered.
With the start of these conversations, it has created a state of a stalemate within the discipline of genetic editing where there is little progress happening compared to before. This is because lots of our strongest resources are currently in use fighting for a technology that has the potential to save countless lives.
Use of Modern Genetic Advancement
Life-changing companies like Lumina, CRISPR, 23 and Me, and Foundation Medicine are at the cutting edge of genomic technology and disrupting the field of health care.
Foundation Medicine is one of these companies that I have had a particular interest in because of their specific use cases in the current field. They are a company that uses information from genetic sequencing to try to prescribe the best and most efficient therapies for cancer within patients. They attempt to use your uniquely sequenced genes to prescribe precision treatments like drugs. One example of this is of Christene Bray. She was a mother of two children, who was diagnosed with breast cancer and her doctors could not find a therapy that would fix the tumor. With the help of Foundation Medicine, and sequencing her genes, they found a niche drug that perfectly worked with her body to put her back into remission and successfully fight off cancer. She could successfully live to see her children graduate instead of scarring them for life.
Genetic sequencing is saving lives and it is most definitely important for everyone to understand their options for treatments. In the future, as we potentially refine this technology, thousands of current issues people face will never be seen again. Let’s embrace and not deny our future. We can live longer and better lives with the help of our genome instead of avoiding it!
